Can FC Dallas remain MLS' best team without their best player, Mauro Diaz?

What happens to the best team in MLS when it loses its best player going into the playoffs? That's the question FC Dallas are still trying figure out.

FC Dallas haven't had much time to adjust to life without Mauro Diaz since he was injured in stoppage time of their second-to-last match of the regular season. Diaz has been their best player, and a relatively stagnant scoreless draw to end the regular season against the LA Galaxy without him last week doesn't inspire much confidence.

Now, with the Seattle Sounders next as FC Dallas start their MLS Cup playoffs (tonight, 9:30 p.m. ET, FS1), coach Oscar Pareja needs to devise a new way for Dallas to create chances. With away goals as a tiebreaker in the two-leg series of the MLS Cup conference semifinals, FCD can't afford not to create good chances in Seattle tonight.

Against the Galaxy a week ago, Pareja shifted Dallas' system from a 4-2-3-1 that plays through Diaz in the central No. 10 spot to a 4-4-2, where they instead looked to sit back and counterattack. While their defense was strong as usual, their attack was lacking and they didn't create enough quality chances.

On paper, though, the 4-4-2 should play to the strengths of the rest of the squad on the field, if they can get it right. Defensively, Dallas is one of the league's best teams with the centerback pairing of Matt Hedges and Walker Zimmerman representing perhaps the best tandem in MLS. Led by defensive midfielder Kellyn Acosta, Dallas is able to sit back and absorb pressure, waiting for the counter. A little further up the field, strikers Maxi Urruti and Tesho Akindele have blazing quick speed that is deadly on transition, and instead of going through the middle with Diaz, they can use the flanks.

But there wasn't nearly enough of the interchange and wide play against the Galaxy last week to make it effective. That meant not enough chance creation — Dallas did have their share of shots in LA, but they weren't good ones, with just two of 13 landing on target and many of them taken outside the 18-yard box. Part of that was the lack of a central player, like a Diaz, underneath Urruti and Akindele guiding the attack.

Compounding the questions about FC Dallas using a 4-4-2 is that Akindele has been having a bit of trouble making an impact lately. He hasn't scored in his last eight games, half of them starts, and Pareja doesn't seem likely to pair Urruti with anyone else up top, which could end up being a mistake.

Pareja does have another option we know he is willing to use, though. In Guatemala for CONCACAF Champions League a week and a half ago, Pareja didn't change FCD's preferred system at all and instead just slotted Mauro Rosales into Diaz's spot. The veteran is no Diaz, who is maybe the best playmaker in the league, but Rosales is solid in the middle and he can distribute the ball well.

Still, the Seattle Sounders are a couple steps up from the Guatemalan side CD Suchitepequez. It will be difficult for Pareja to take any lessons from Dallas' 5-2 win in Guatemala and try to apply them to a playoff game in Seattle.

What we at least know is that Pareja sees more than one way forward, and he may still have some new changes in mind yet. After all, Diaz is an irreplaceable player and missing out on his chance creation could leave FCD vulnerable. It's too important not to address. The Sounders' defense, like FCD's, is very good and shots could come at a premium.

FC Dallas, the 2016 Supporter's Shield winners, were the best team of the regular season, but it will soon be apparent how much of that had to do with Diaz. Whether they can be the best team of the postseason probably depends on figuring that out.

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